FibonnaciCalculateTag.java.
- By Dion Almaer
- June 24, 2001
Enterprise Java
Tag Libraries: JSPs in the Enterprise
by Dion Almaer
Listing 7. FibonnaciCalculateTag.java.
package com.customware.fib;
import java.io.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
/**
* This class defines a custom JSP tag that handles fibonnaci.
* Usage:<BR>
* <fib:calculate number="2"><BR>
* [this is part of the body and will be deleted. used for designers]<BR>
* </fib:calculate>
*/
public class FibonnaciCalculateTag extends TagSupport {
private int number = 0;
// -- Setters and getters for the attributes
public void setInput(String input) {
try {
this.number = Integer.parseInt( input.trim() );
} catch (NumberFormatException e) { }
}
public int getInput() { return this.number; }
// -- TAG stuff
public int doStartTag() throws JspException {
return SKIP_BODY;
}
public int doEndTag() throws JspException {
// Reformat the body with the calculation inputted
Fibonnaci fib = new Fibonnaci();
int output = fib.calculateFibonacci( this.getInput() );
// Write contents of 'output' to the parent's out stream.
try {
pageContext.getOut().println( output );
} catch (IOException ioe) {}
return EVAL_PAGE;
}
}
About the Author
Dion Almaer is a senior consultant for CustomWare in Boulder, CO. He can be reached at [email protected].